U.S. patent application number 15/342222 was filed with the patent office on 2017-05-25 for depolymerization processes, apparatuses and catalysts for use in connection therewith.
The applicant listed for this patent is Pravansu S. Mohanty, Swaminathan Ramesh. Invention is credited to Pravansu S. Mohanty, Swaminathan Ramesh.
Application Number | 20170144127 15/342222 |
Document ID | / |
Family ID | 46207742 |
Filed Date | 2017-05-25 |
United States Patent
Application |
20170144127 |
Kind Code |
A1 |
Mohanty; Pravansu S. ; et
al. |
May 25, 2017 |
DEPOLYMERIZATION PROCESSES, APPARATUSES AND CATALYSTS FOR USE IN
CONNECTION THEREWITH
Abstract
The present disclosure generally relates to processes,
apparatuses and custom catalysts designed to depolymerize a
polymer. In one embodiment, the present invention relates to a
de-polymerizing apparatus, catalysts and reaction schemes to obtain
useful monomers including fuel products by "in situ" reactions
using coupled electromagnetic induction.
Inventors: |
Mohanty; Pravansu S.;
(Farmington Hills, MI) ; Ramesh; Swaminathan;
(Farmington Hills, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Mohanty; Pravansu S.
Ramesh; Swaminathan |
Farmington Hills
Farmington Hills |
MI
MI |
US
US |
|
|
Family ID: |
46207742 |
Appl. No.: |
15/342222 |
Filed: |
November 3, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13992617 |
Aug 15, 2013 |
9505901 |
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PCT/US2011/063947 |
Dec 8, 2011 |
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15342222 |
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61420961 |
Dec 8, 2010 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08J 2300/00 20130101;
B01J 23/466 20130101; B01J 2219/0854 20130101; Y02P 20/52 20151101;
B01J 23/34 20130101; B01J 19/088 20130101; B01J 2219/0879 20130101;
C07C 4/22 20130101; B01J 2219/0894 20130101; B01J 2219/00033
20130101; C08J 11/16 20130101; B01J 8/003 20130101; B01J 19/12
20130101; Y02W 30/62 20150501; B01J 8/10 20130101; B01J 2219/0892
20130101; Y02W 30/705 20150501; B01J 8/087 20130101; C08J 11/10
20130101; C07C 4/22 20130101; C07C 11/04 20130101; C07C 4/22
20130101; C07C 11/06 20130101 |
International
Class: |
B01J 19/12 20060101
B01J019/12; C08J 11/10 20060101 C08J011/10 |
Claims
1. A method of depolymerizing polymers, the method comprising the
steps of: (i) providing one or more polymer starting materials, or
feed materials; (ii) providing a reactor to depolymerize the one or
more polymer starting materials, or feed materials, into one or
more monomers; (iii) heating the one or more polymer starting
materials, or feed materials, at a rate of from about 1.degree.
C./second to about 1000.degree. C./second; and (iv) providing an
electromagnetic induction field to facilitate the depolymerization
of the one or more polymer starting materials, or feed materials,
into their constituent monomers, wherein the method utilizes one or
more catalysts that permit in situ reactions to yield one or more
functional monomers.
2. The method according to claim 1, wherein the in situ reaction
involves at least one catalytic composition supported on at least
one solid substrate.
3. The method according to claim 1, wherein the method further
comprises the step of: (v) selectively harvesting at least one of
the monomers produced by the method or converting at least one of
the monomers into one or more stable value added products.
4. The method according to claim 1, wherein the reactor is provided
with an electromagnetic source to inductively couple with the
mixing device and heat one or more polymer starting materials, or
feed materials, to a desired temperature.
5. The method according to claim 1, wherein the reactor is provided
with a plasma device in combination with an electromagnetic source
to inductively couple with the mixing device and heat the one or
more polymer starting materials, or feed materials to a desired
temperature.
6. The method according to claim 1, wherein the one or more
catalysts sites are alkaline in nature, acidic in nature, or a
combination thereof.
7. The method according to claim 1, wherein the one or more
catalysts are applied on one or more solid supports by an additive
deposition process.
8. The method according to claim 1, wherein the one or more
catalysts are synthesized on one or more solid supports by
thermo-chemical processes.
9. The method according to claim 1, wherein the one or more
catalysts are nanoscale catalysts.
10. The method according to claim 9, wherein the one or more
nanoscale catalysts enhance the depolymerization process and
perform additional chemical transformations to yield and/or obtain
functional chemicals.
11. The method according to claim 1, wherein the one or more
monomers produced by the method according to claim 1 are the basic
components which were used to form the one or more polymer starting
materials, or feed materials.
12. The method according to claim 1, wherein the method further
comprises the step of: reacting one or more of the monomers to
yield one or more functional chemicals.
13. The method according to claim 1, wherein the heating rate in
Step (iii) is about 50.degree. C./second to about 500.degree.
C./second.
14. The method according to claim 1, wherein the heating rate in
Step (iii) is about 100.degree. C./second to about 200.degree.
C./second.
15. The method according to claim 1, wherein the heating rate in
Step (iii) is about 200.degree. C./second.
16. A method of depolymerizing polymers, the method comprising the
steps of: (a) providing one or more polymer starting materials, or
feed materials; (b) providing a reactor to depolymerize the one or
more polymer starting materials, or feed materials, into one or
more monomers; (c) heating the one or more polymer starting
materials, or feed materials, at a rate of from about 10.degree.
C./second to about 1000.degree. C./second; (d) providing an
electromagnetic induction field to facilitate the depolymerization
of the one or more polymer starting materials, or feed materials,
into their constituent monomers; and (e) selectively harvesting at
least one of the monomers produced by the method or converting at
least one of the monomers into one or more stable value added
products, wherein the method utilizes one or more catalysts that
permit in situ reactions to yield one or more functional
monomers.
17. A method of depolymerizing polymers, the method comprising the
steps of: (I) providing a polymer starting material, or feed
material; (II) providing a reactor to depolymerize the polymer
starting material, or feed material, into a constituent monomer;
(III) heating the one or more polymer starting materials, or feed
materials, at a rate of from about 10.degree. C./second to about
1000.degree. C./second; and (IV) providing an electromagnetic
induction field to facilitate the depolymerization of the material,
or feed material into its constituent monomer, wherein the method
achieves a yield of constituent monomer of at least about 80 weight
percent based on the extractable weight percent value contained in
the polymer starting material, or feed material, subjected to
depolymerization.
Description
RELATED APPLICATION DATA
[0001] This application claims the benefit of U.S. Utility
application Ser. No. 13/992,617 filed on Aug. 15, 2013 and entitled
"Deploymerization Processes, Apparatuses and Cataylsts for Use In
Connection Therewith", International Application No.
PCT/US2011/06394 filed on Dec. 8, 2011 and entitled
""Deploymerization Processes, Apparatuses and Cataylsts for Use In
Connection Therewith"", and U.S. Provisional Application No.
61/420,961, filed on Dec. 8, 2010 and entitled "Customized
Catalysts and Application Apparatus for Depolymerization
Reactions," the entire disclosure of which is incorporated herein
by reference.
FIELD OF THE INVENTION
[0002] The present disclosure generally relates to processes,
apparatuses and custom catalysts designed to depoiymerize a
polymer. in one embodiment, the present invention relates to a
de-polymerizing apparatus, catalysts and reaction schemes to obtain
useful monomers including fuel products by "in situ" reactions
using coupled electromagnetic induction.
BACKGROUND OF THE INVENTION
[0003] Addition polymers (in contrast to condensation polymers) can
be depoiymerized by heat to simpler monomers and its oligomers. Use
of one or more catalysts can result in lower reaction temperatures
at which the depolymerization reaction occurs, as well as provide
some amount of control on the depolymerized product mixture.
However, the product mix will always contain large quantities of
unsaturated compounds that will affect its stability on exposure to
air. Also, without further purification steps such as one or more
fractionations, the depolymerized reaction product cannot be used
directly.
[0004] Various plastics are examples of compounds produced by
addition polymerization reactions. Typically, such plastics are
produced from non-renewable petroleum resources and are often
non-biodegradable. In the United States, such plastics like
polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC) and
polystyrene (PS) are produced in amounts exceeding 115,000 million
pounds annually. Plastics are used in many industries to form
products for sale in both industrial and residential markets. In
industrial markets, these polymers are used to form packaging,
insulation, construction products, and the like. In residential
markets, these polymers are used to form bottles, containers, and
the like.
[0005] Catalytic depolymerization of high and low density
polyethylene, polypropylene and polystyrene into diesel like fuel
is well known in the literature, both published and patented.
Usability of such fuel is hampered by the fact that the presence of
large amounts of unsaturated products reduces the stability
(formation of brown polymer products) of the diesel fuel produced
thereby and, as such, necessitates the need for a separate
hydrogenation step to improve the stability and calorific value of
the diesel so produced.
[0006] Accordingly, the depolymerization of polymers requires a
careful selection of catalysts, processing as well as separation
scheme to extract valuable diesel like fuel. FIG. 1 presents a gas
chromatograph illustrating the identity and relative quantities of
various monomers formed from pyrolysis of polyethylene and
polypropylene. The monomers include alkanes, alkenes, and alkynes
or dienes having from 2 to 40 carbon atoms wherein the alkanes are
colored green, the alkenes are colored red, and the alkynes and
dienes are colored blue.
[0007] Besides the addition polymers, there are condensation
polymers, which include polyesters (PET), polyurethanes (PU),
nylons or polyimides and the like. There are also thermoset
polymers (example automotive coatings), which are three dimensional
polymer networks formed by cross-linking reactions of the linear
polymers.
[0008] In contrast to polyethylene, polypropylene and other
polyenes, condensation polymers and thermosets cannot be
"depolymerized" using thermal energy. Instead, one must rely on
extensive chemical reactions to convert such products back to their
starting materials and, as such, this is economically prohibitive
to perform.
[0009] Given the above, only a small fraction of the polymers
produced are recycled and re-used. Polymers that are not recycled
and re-used present potential environmental pollution risks when
discarded, are not utilized for energy or raw materials, and
contribute to an increased reliance on non-renewable petroleum
resources.
SUMMARY OF THE INVENTION
[0010] The present disclosure generally relates to processes,
apparatuses and specially designed catalysts designed to
depolymerize a polymer. In one embodiment, the present invention
relates to a de-polymerizing apparatus, catalysts and reaction
schemes to obtain useful monomers including fuel products by "in
situ" reactions using coupled electromagnetic induction.
[0011] This present disclosure provides for apparatus, reaction
schemes and reaction conditions comprising the use of coupled
electromagnetic induction and customized catalyst materials to
depolymerize all kinds of polymers to useful monomers including
fuel type mixtures. The method offers unique advantages in terms of
product selectivity and process efficiency.
[0012] Further, in one embodiment the methods of the present
invention form, under certain conditions, high purity monomers that
may be used as starting materials for highly value added functional
monomers. In one embodiment, these functional monomers can be
formed in situ in the reactor thus making the process
economical.
[0013] In another embodiment, the method of the present invention
includes the step of introducing a polymer into a reactor, and
depolymerizing the polymer in the vessel while in the presence of
at least one catalyst. As will be discussed below, the methods of
the present invention can, in one embodiment, utilize one or more
customized catalyst designed to facilitate in situ depolymerization
reactions.
[0014] In one embodiment, the present invention relates to a method
of depolymerizing polymers, the method comprising the steps of: (i)
providing one or more polymer starting materials, or feed
materials; (ii) providing a reactor to depolymerize the one or more
polymer starting materials, or feed materials, into one or more
monomers: (iii) heating the one or more polymer starting materials,
or feed materials, at a rate of from about 10.degree. C./second to
about 1000.degree. C./second; and (iv) providing an electromagnetic
induction field to facilitate the depolymerization of the one or
more polymer starting materials, or feed materials, into their
constituent monomers, wherein the method utilizes one or more
catalysts that permit in situ reactions to yield one or more
functional monomers.
[0015] In another embodiment, the present invention relates to a
method of depolymerizing polymers, the method comprising the steps
of: (a) providing one or more polymer starting materials, or feed
materials; (b) providing a reactor to depolymerize the one or more
polymer starting materials, or feed materials, into one or more
monomers; (c) heating the one or more polymer starting materials,
or feed materials, at a rate of from about 10.degree. C./second to
about 1000.degree. C./second: (d) providing an electromagnetic
induction field to facilitate the depolymerization of the one or
more polymer starting materials, or feed materials, into their
constituent monomers; and (e) selectively harvesting at least one
of the monomers produced by the method or converting at least one
of the monomers into one or more stable value added products,
wherein the method utilizes one or more catalysts that permit in
situ reactions to yield one or more functional monomers.
[0016] In still another embodiment, the present invention relates
to a method of depolymerizing polymers, the method comprising the
steps of: (I) providing a polymer starting material, or feed
material; (II) providing a reactor to depolymerize the polymer
starting material, or feed material, into a constituent monomer;
(III) heating the one or more polymer starting materials, or feed
materials, at a rate of from about 10.degree. C./second to about
1000.degree. C./second; and (IV) providing an electromagnetic
induction field to facilitate the depolymerization of the material,
or feed material into its constituent monomer, wherein the method
achieves a yield of constituent monomer of at least about 80 weight
percent based on the extractable weight percent value contained in
the polymer starting material, or feed material, subjected to
depolymerization.
[0017] Further areas of applicability will become apparent from the
description provided herein. The description and specific examples
in this summary are intended for purposes of illustration only and
are not intended to limit the scope of the present disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The drawings described herein are for illustrative purposes
only of selected embodiments and not all possible implementations,
and are not intended to limit the scope of the present disclosure.
For purposes of clarity, not every component is labeled in every
figure, nor is every component of each embodiment of the disclosure
shown.
[0019] FIG. 1 is a gas chromatograph illustrating identity and
relative quantities of monomers formed from pyrolysis of
polyethylene and polypropylene as the exemplary polymer of the
present invention;
[0020] FIG. 2 is a block diagram illustrating an embodiment of the
present invention comprising a feeder, a reactor with coupled
electromagnetic induction field and optional customized catalysts
through which H.sub.2 and N.sub.2 gasses as the reducing agents,
and a distillation columns and the depolymerized polymer flow,
showing recycling of the polymers and formation of monomers;
[0021] FIG. 3 is a schematic view of an exemplary embodiment of the
present disclosure comprising the processing apparatus scheme of
FIG. 2 with an induction coil;
[0022] FIG. 4 is a schematic view of an exemplary embodiment of the
mixing device inside the processing apparatus assembly of FIG. 3
comprising impeller blades coated with designed catalysts;
[0023] FIG. 5 is an exemplary result demonstrating selective
harvesting of starting monomers, according to the principles of the
present teachings;
[0024] FIG. 6 is an exemplary result demonstrating selective
harvesting of starting monomers in the absence of any catalysts,
according to the principles of the present teachings;
[0025] FIG. 7 is an exemplary result demonstrating harvesting of
mixed monomers in the presence of catalysts, according to the
principles of the present teachings;
[0026] FIG. 8 is an exemplary result demonstrating harvesting of
mixed monomers from mixed plastics in the presence of catalysts,
according to the principles of the present teachings;
[0027] FIG. 9A a schematic view of an exemplary embodiment of the
spray device for applying catalysts onto the impeller blades of
FIG. 4:
[0028] FIG. 9B is a schematic view of an exemplary embodiment of
the spray device of FIG. 9A comprising a combustion flame
system;
[0029] FIG. 9C is a schematic view of an exemplary embodiment of
the precursor feed device of FIG. 9A comprising three liquid
precursor reservoirs with a mixing and pumping system;
[0030] FIG. 9D is a schematic view of catalytic material film being
deposited employing particles synthesized by plasma from liquid
and/or gaseous precursors according to the principles of the
present teachings;
[0031] FIG. 10A is a block diagram illustrating an embodiment of
the present invention comprising three customized catalyst
zones;
[0032] FIG. 10B is a schematic view of an exemplary embodiment of
the present disclosure comprising the processing apparatus scheme
of FIG. 10A with an induction coil;
[0033] FIG. 10C is a schematic view of an impeller with graded
catalysts according to the principles of the present teachings;
[0034] FIG. 10D is a schematic view of an Impeller filled with
zeolite pellets with graded catalysts of FIG. 10C according to the
principles of the present teachings;
[0035] FIG. 11 is a perspective view of a system illustrating a
plasma device being utilized to heat the plastic; and
[0036] Corresponding reference numerals indicate corresponding
parts throughout the several views of the drawings.
DESCRIPTION OF THE INVENTION
[0037] The present disclosure generally relates to processes,
apparatuses and specially designed catalysts designed to
depolymerize a polymer. In one embodiment, the present invention
relates to a de-polymerizing apparatus, catalysts and reaction
schemes to obtain useful monomers including fuel products by "in
situ" reactions using coupled electromagnetic induction.
[0038] Non-limiting embodiments of the present disclosure will be
described by way of example with reference to the accompanying
Figures, which are schematic and are not intended to be drawn to
scale.
[0039] Referring initially to FIG. 2, the block diagram illustrates
one embodiment of the present disclosure in which shredded polymers
are continuously fed by a feeder into a reactor along with one or
more inert gases selected from N.sub.2, helium, or other inert gas
to keep the atmosphere inert (the gas feed may also contain H.sub.2
gas as the reducing agent if needed). The polymer starting
material, or feed material, is subject to a coupled electromagnetic
induction energy field resulting in fusion and depolymerization. In
one instance, this embodiment can be conducted in the presence of
one or more catalysts compounds that will be described in detail
below. In another embodiment, the above process can be conducted in
the absence of a catalyst. In both instances, the polymer
compositions so treated are converted into useful functional
monomers. Regarding the strength of the electromagnetic field
utilized to provide the coupled electromagnetic induction energy
field such a parameter will vary depending upon the amount of
polymer starting material, or feed material present, the size of
the reactor, the process rate, etc. Accordingly, the present
invention is not limited to any one electromagnetic field
strength.
[0040] The polymer feed material that can be used in conjunction
with the present invention can be any thermoplastic or thermoset
known in the art. In one embodiment, the polymer feed material is a
polymerization product of monomers including, but not limited to,
aliphatic monomers, aromatic monomers, and/or suitable combinations
of any two or more thereof. In another embodiment, the polymer feed
material is the polymerization product of monomers including
unsaturated monomers such as alkenes and dienes having
carbon-carbon double bonds, alkynes having carbon-carbon triple
bonds, and styrene monomers, and/or suitable combinations of two or
more thereof. As such, the polymer feed material utilized in
conjunction with the present invention can include one or more
polyethylenes (PE), one or more polypropylenes (PP), one or more
polyvinyl chlorides (PVC), one or more polystyrenes (PS), and/or
suitable combinations of any two or more thereof. In one
embodiment, the polymer feed materials of the present invention
have recycle codes of 2, 3, 4, 5 and 6. In still another
embodiment, the polymer feed material of the present invention is a
condensation polymer formed from reaction of one or more
polyalcohols with one or more polycarboxy acids in the absence of
water. As would be appreciated by those of skill in the art, these
are polyesters and have a recycle code of 1. The polymer feed
material can, in another embodiment, be one or more polyurethanes,
made by reacting at least one isocyanate with at least one alcohol.
The polymer feed material can also be a nylon, which is a
polyimide, formed from the reaction of one or more polycarboxylic
acids with one or more polyamines. It should be noted that the
polymer feed material of the present invention is not limited to
just the above examples. Rather, the polymer feed material of the
present invention can also be selected from a myriad of other
polymers formed from the reaction of two functional groups with the
elimination of simple molecules (condensation), which correspond to
recycling code 7. The polymer feed material of the present
invention can, in one embodiment, be atactic, isotactic or
syndiotactic. For non-limiting illustrative purposes only, the
chemical structures of various polymers are shown below:
##STR00001##
wherein n may be any integer equal to two or more.
[0041] The polymer feed material is typically supplied in various
commercial product forms. Such forms include, but are not limited
to, containers, packaging, insulation, construction products,
and/or combinations of any two or more thereof. However, it is
contemplated that the polymer feed material can be in any form.
Such forms include, but are not limited to, any commercial product
form, commercial product rejects (i.e., defective products that
would otherwise be disposed of), and/or left over polymer from a
manufacturing process (e.g., an extrusion process, blow molding
process, etc.). In one embodiment, if so desired and/ort necessary
prior to introduction of the polymer feed material into the
reactor, the polymer feed material can be processed via one or more
physical and/or chemical treatments to ease introduction into the
reactor. If the polymer feed material is processed with one or more
physical treatments, the polymer can be cleaned to remove dirt,
oil, grease, detergents, food, exogenous plant and animal
contaminants, and/or combinations of any two or more thereof. The
polymer feed material can be cleaned with any method known to those
of skill in the art. In one embodiment, the polymer feed material
is cleaned using pressurized water jets, floatation, surfactants,
scrubbers and the like, and/or combinations of two or more thereof.
The polymer feed material can also be reduced in size through any
method known in the art including, but not limited to, shredding,
grinding, heating, melting, burning, smashing, dissolving, tearing,
crushing, and/or combinations of two or more thereof. If reduced in
size, the polymer feed material can be reduced to any size
including, but not limited to, powder, nanopowder, pellets, etc. As
used herein the word, or prefix, "nano" refers to any object having
a size, or even just one dimension, of less than about 1,000
nanometers, less than about 750 nanometers, less than about 500
nanometers, less than about 250 nanometers, less than about 100
nanometers, less than about 50 nanometers, less than about 25
nanometers, less than about 10 nanometers, less than about 5
nanometers, or even less than about 1. Here, as well as elsewhere
in the specification can claims, individual range values, or
limits, can be combined to form additional and/or non-disclosed
open and closed ranges. The polymer feed material can also be
physically treated through stirring, mixing, sonicating, by using
radio waves, magnetic energy, and light energy, and/or combinations
of two or more thereof. If the polymer feed material is processed
with chemical treatments, the polymer feed material can be combined
with one or more catalysts, one or more enzymes, one or more
fillers, one or more acids, one or more bases, one or more salts,
one or more cationic and anionic compounds, one or more processing
agents, and/or combinations of any two or more thereof. In one
embodiment, the polymer feed material of the present invention is
cleaned, shredded, and melted.
[0042] Referring now to the step of introducing the polymer feed
material (or polymer material for recycling) into the reactor, the
polymer feed material can be introduced into the reactor in any
setting and in any amount. The polymer feed material can be
introduced into the reactor in laboratories utilizing small amounts
on a gram and smaller scale and in industrial recycling facilities
utilizing large amounts on a kilogram to kiloton, or even larger
scale. The reactor can be any vessel known in the art and can
include one or more laboratory and/or industrial size vessels and
reactors. In one embodiment, the method is utilized on a kilogram
to kiloton (or even larger scale) scale in any suitably sized
industrial recycling facility (or facilities) utilizing a suitable
designed industrial size reactor, or reactors.
[0043] The reactor can be any reactor known in the art including,
but not limited to, screw reactors, plug reactors, and combinations
of any two or more thereof. The reactor can also be operated in any
type of mode including, but not limited to, batch and continuous
modes. In one embodiment, the reactor is operated in continuous
mode to reduce energy consumption, operating costs, size of the
reactor, running time, down time, etc. The reactor may further be
operated at any temperature.
[0044] After the polymer feed material (or polymer material to be
recycled and/or depolymerized) is introduced into the reactor, the
method comprises the step of depolymerizing the polymer, as
previously discussed above. The polymer feed material can be
fragmented by any method known in the art. It is contemplated that
the polymer feed material can be decomposed by heating, actinic and
microwave radiation, or combinations of any two or more thereof. In
one embodiment, the polymer feed material is decomposed by heating
with conventional methods, with microwave radiation, with resistive
heating, utilizing fossil fuels, with induction heaters, with
plasma, with solar energy, with radioactive energy, or combinations
of any two or more thereof. In still another embodiment,
depolymerization is accomplished with at least one coupled
electromagnetic induction field directly applied to the mixing
device/polymers using the setup described below. When the polymer
feed material is decomposed, the polymer feed material is
preferably at least partially reverse polymerized (i.e., broken
down) into monomers.
[0045] With reference to FIG. 3, in one embodiment of the present
invention, an apparatus 10 for carrying out one or more methods in
accordance with the disclosure contained herein comprises a feeder
12, a motor 13, a reactor 14 with internal mixing device, and
condensers 16. Polymer feed material (or polymer material to be
recycled and/or depolymerized) from feeder 12 is continuously fed
into rector 14, whose internal mixing device couples with the
electromagnetic induction field applied via induction coil 15.
Referring to FIG. 4, the internal mixing device comprises of
impeller assembly 20 that is designed to function with and/or
facilitate the use of electromagnetic induction coupling and thus
is energized upon application of induction current through coil 15.
The impeller 20 mixes and heats the incoming polymer simultaneously
ensuring uniform temperature in the feed material.
[0046] In one embodiment, the polymer feed material is heated. If
so heated, the polymer feed material can be heated to any desired
temperature. In one embodiment, the polymer feed material is heated
to a temperature of from about 25.degree. C. to about 1000.degree.
C., or from about 100.degree. C. to about 700.degree. C., or even
from about 200.degree. C. to about 400.degree. C. Here, as well as
elsewhere in the specification can claims, individual range values,
or limits, can be combined to form additional and/or non-disclosed
open and closed ranges. In another embodiment, the polymer feed
material can be heated at any rate. In one embodiment, the polymer
feed material is heated at a rate of from about 10.degree.
C./second to about 1000.degree. C./second, or from about 50.degree.
C./second to about 500.degree. C./second, or even from about
100.degree. C./second to about 200.degree. C./second. Here, as well
as elsewhere in the specification can claims, individual range
values, or limits, can be combined to form additional and/or
non-disclosed open and closed ranges. With the setup described
above, one can, for example, achieve a heating rate of from about
10.degree. C./second to about 1000.degree. C./second, or even about
200.degree. C. per second.
[0047] If the polymer feed material is heated at a rate of from
about 100.degree. C. to about 1000.degree. C./second, especially in
an absence of air, the polymer is subject to pyrolysis. If the
polymer feed material is heated at a rate of from about 25.degree.
C./second to 100.degree. C./second, the polymer is subject to
thermolysis. As is known in the art, pyrolysis includes rapid
heating of a polymer material to at least partially reverse
polymerize the polymer and form/yield monomers. Similarly, as is
also known in the art, thermolysis includes the slower heating of a
polymer material to at least partially reverse polymerize the
polymer and form monomers. As is shown in FIG. 1, if the polymer
feed material includes pyrolyzed polyethylene and/or polypropylene,
alkanes, alkenes, and alkynes or dienes having between 2 and 40
carbon atoms are produced, wherein the alkanes are colored green,
the alkenes are colored red, and the alkynes and dienes are colored
blue. After formation, the monomers can be removed by boiling or
with a stream of Inert gas including, but not limited to, helium,
neon, argon, krypton, xenon, nitrogen, hydrogen, or combinations of
any two or more thereof.
[0048] When a polymer feed material is processed using the coupled
electromagnetic induction setup as described herein, a different
result is observed as illustrated in FIGS. 5 and 6. Instead of a
varying distribution of a number of different alkenes, alkanes and
dienes, the major product yielded in these circumstances is alkene
monomers. This results in over about 80 percent to about 85 percent
of the products produce as a gas. A few percentages of liquid and
solid products are also found.
[0049] The coupled electromagnetic induction heat processing using
the setup discussed herein permits one to convert a polymer to its
individual base monomer while realizing both a high yield and
specificity for the particular monomer that gave rise to the
polymer material being depolymerized. For example, polyethylene
will yield ethylene monomer at a yield rate of about 80 percent or
greater. A polypropylene will yield propylene monomer at a yield
rate of about 80 percent or greater. A combination of polyethylene
and polypropylene will yield a mixture of ethylene and propylene
monomers in the ratio of such materials in the polymer feed
material at a yield rate of about 80 percent or greater. A
polystyrene will yield styrene monomer at a yield rate of about 80
percent or greater. Similarly, a PVC will yield vinyl chloride
monomer at a yield rate of about 80 percent or greater.
[0050] When coupled electromagnetic induction heating is employed
to depolymerize a polymer in presence of a catalyst a somewhat
different behavior is observed. One still obtains a majority of the
reaction products as individual monomers (see FIG. 7), but one sees
more waxy solid products formed as well (see FIG. 8). While not
wishing to be bound to any one theory, it is postulated that there
are two different reaction pathways occurring, the catalyzed
reaction tending to yield (or be more favorable towards) fuel like
products. As can be seen there from, the product distribution of
FIG. 8 looks similar to that of FIG. 1 which is obtained via the
thermolysis of various polymers that are in the case of FIG. 8
utilized as the starting or feed material for the present
invention.
[0051] The coupled electromagnetic induction principle discussed
herein permits one to depolymerize a urethane into an isocyanate
(and/or polyisocyanate) and alcohol functional monomer or a polyol.
By effective distillation of one of the products, each of the
reactive compounds can be obtained in high yields. Similarly, a
polyester will yield an anhydride of a dicarboxylic acid and a
polyol if during the process enough water is introduced
catalytically and the products distilled off. Similar
depolymerization of thermosets can be envisaged and while not
wishing to be bound to any one theory or chemical mechanism,
possible chemistries are depicted below:
##STR00002##
[0052] As the polymer feed material, or starting material, is
depolymerized, the method of the present invention can also include
the step of monitoring the formation of monomers. The monomers can
be monitored online, offline, or through a combination of both
online and offline monitoring. Also, the step of monitoring can
include utilizing any monitoring technique known by those of skill
in the art. The monitoring technique can include, but is not
limited to, spectroscopy and/or chromatography. If the monitoring
technique includes spectroscopy, the spectroscopy can include mass,
infrared, atomic emission, atomic absorption, nuclear magnetic
resonance, Ramen, fluorescence, x-ray, atomic fluorescence, plasma
emission, direct-current plasma, inductively-coupled plasma, laser
induced breakdown, laser-induced plasma, microwave-induced plasma,
spark and/or arc, UV, photoemission, force, dielectric, circular
dichroism, rotational, vibrational, rigid rotor, EPR, spectral
power distribution, metamerism, spectral reflectance, acoustic,
dynamic mechanical, electron energy loss, and Auger electron,
spectroscopies, and combinations of any two or more thereof. If the
monitoring technique includes chromatography, the chromatography
can include gas, liquid, ion-exchange, affinity, thin layer,
supercritical fluid, and column, chromatographles, and combinations
of any two or more thereof.
[0053] The method of the present invention can also include the
step of introducing a catalyst into the reactor. In one embodiment,
the catalyst can be introduced into the reactor at any point in the
method. In one instance, if one or more catalysts are introduced,
the one or more catalysts are introduced after the polymer feed
material (or polymer starting material) is introduced into the
reactor and as the polymer feed material (or polymer starting
material) is decomposed. In another embodiment, the one or more
catalysts are bound to one or more substrates or phase supports
inside the reactor and the polymer feed material (or polymer
starting material) is introduced over the one or more catalysts in
a molten and/or gaseous form. With particular reference to FIG. 4,
the catalyst 23 is applied on the impeller blade 22 of the assembly
20.
[0054] As is known in the art, catalysts can be used in two
different ways. In general, the catalysts can effect the
polymerization of olefins to polymers having high molecular weights
and highly ordered structures. Conversely, the one or more
catalysts can effect the reverse polymerization (i.e., the
decomposition or unzipping of polymers) thereby catalyzing the
break down of the polymers in the polymer feed material (or polymer
starting material) into one or more monomers and break apart the
highly ordered structures. In the process and system/apparatus of
the present invention, one or more catalyst is used for reverse
polymerization.
[0055] Under the effects of coupled electromagnetic induction
field, the one or more polymers in the polymer feed material (or
polymer starting material) is shown to depolymerize completely to
its starting monomers. Added catalysts are present, in one
embodiment, to react/catalyze the monomers in situ to generate
value added functional monomers.
[0056] In one embodiment, it is possible and/or desirable to add
water to the process/method of the present invention so as to
facilitate the conversion of various double bond-containing of an
alkene compounds to generate an alcohol, oxygen to generate an
epoxide and further react/catalyze a compound to a diol or react
with oxygen partially and alcohol to generate an acrylic monomer,
all of which are commercially more valuable than the alkenes
themselves.
[0057] In another embodiment, the presence of one or more catalysts
can influence the reaction pathway and the present invention yields
products with a broader distribution (see FIG. 8). In these
embodiments, the presence of one or more hydrogenation catalysts
will lead to fuels with higher energy densities.
[0058] Non-limiting examples of such post transformational
catalytic reactions are illustrated below:
##STR00003##
[0059] The one or more catalysts can be any catalysts known in the
art. For example, in one embodiment the one or more catalysts can
be chiral or achiral, can be symmetric or asymmetric, and/or can be
homogeneous or heterogeneous. The one or more catalysts can also
include any organic or inorganic moieties known in the art. In one
embodiment, the one or more catalysts will facilitate, or catalyze,
preferentially the reaction of one or more monomers initially
formed by the depolymerization reaction of the present invention to
obtain other value added compounds. In one embodiment, the one or
more catalysts are present in an amount of less than or equal to
about 500 parts per 100 parts by weight of the one or more polymer
feed materials, or starting materials. In another embodiment, the
one or more catalysts are present in an amount from about 0.1 part
per one million parts by weight of the polymer feed material, or
starting material, to about 100 parts of the catalyst per 100 parts
by weight of the polymer feed material, or starting material. In
still another embodiment, the one or more catalysts are present in
an amount from about 0.1 part per one million parts by weight of
the polymer feed material, or starting material, to about 20 parts
of the one or more catalysts per 100 parts by weight of the polymer
feed material, or starting material. Here, as well as elsewhere in
the specification can claims, individual range values, or limits,
can be combined to form additional and/or non-disclosed open and
closed ranges.
[0060] For example, an alkene can be converted into an alcohol
(primary or secondary) by addition of water across the double
bonds, either catalyzed by acids or with hydroboration and reaction
with hydrogen peroxide.
[0061] If one or more alkenes are reacted with hydrogen peroxide
catalyzed by nano-structured silver they will be converted into
epoxides in very high yields. These epoxides can further be reacted
with one or more acids to form valuable esters, or reacted with
water to form diols, or reacted under pressure with an acid, or
base, catalyst to form polyols. These transformations are highly
valuable in commodity products like foams, cosmetics etc.
[0062] In another embodiment, the present invention reacts one or
more alkenes with osmium tetroxide or potassium permanganate to
yield one or more diols directly. Again, diols are valuable
chemicals used heavily in automotive and consumer products.
[0063] In still another embodiment, the present invention reacts
propylene partially with 1.5 molecules of oxygen in presence of at
least one molybdenum oxide catalyst to yield an acrylic acid
monomer. As is known in the art, such compounds are very highly
valuable intermediates in the coatings business and in the highly
absorbent diaper industry.
[0064] In still another embodiment, the present invention reduces
one or more double bonds with hydrogen as they are formed using
catalysts like palladium, or one or more catalysts with
customizable alkaline and/or acidic sites in the same molecule, to
yield one or more saturated alkanes. Thus, in this embodiment it is
possible to produce propane or butane from waste polypropylene or
polybutylene polymers.
[0065] Specifically, the various catalysts including the aluminum
and titanium oxides with varying ratios of acidity and alkalinity
are formed and dispersed in nano-dimensional scale on the
electromagnetic induction coupler.
[0066] With particular reference to FIG. 9A, one embodiment of the
present invention is to apply the one or more catalysts using an
appropriate fluid precursor which is injected to a hot gaseous
stream for chemical/thermal treatment and consolidation into the
desired catalyst layer on solid support. The fluid precursors upon
injection into the hot gas pyrolyze in the stream resulting in fine
molten/semi-molten/solid droplets of the desired materials that are
consolidated into a film or particulate form.
[0067] The synthesis schemes of the present disclosure provide
films possessing the desired morphological features, phase and
compositions directly from chemical precursors, and thus, eliminate
processing steps currently practiced in the industry. Further, the
spray deposition techniques of the present invention enable the
creation of geometrically complex coupler. In some embodiments, the
use of fluid precursors where the component ingredients are in a
completely dissolved state ensure homogeneity of component elements
and enhance reaction rates compared to the solid state reactions
commonly practiced in conventional processes, and thus can reduce
the processing time.
[0068] As shown in FIG. 9A, a fabrication apparatus assembly 30
comprises a motion system 32 that mechanically commutes a spray
device 34 to build a uniform film on a target 38, utilizing the
fluid precursors from reservoir 35 in measured quantities via a
pumping system 33. Apparatus assembly 30 can be installed in any
environment.
[0069] In some embodiments of spray device 40 a combustion flame is
employed as illustrated in FIG. 9B. The combustion apparatus can
employ a fuel such as hydrocarbon or hydrogen 42 as well as oxygen
or air 43 to generate a sufficiently hot flame 47. The precursor
material 44 can be injected to the flame axially via injector
element 41 and/or radially via injector element 45 to synthesize
the desired material and consolidate them into a deposit on target
38 according to the principles of the current teachings set forth
herein. The chemical environment of the flame can be adjusted
either to oxygen rich or oxygen lean by adjusting the fuel to air
ratio. Such adjustments can control the chemistry of the target
material.
[0070] Referring to FIG. 9C, a precursor feed assembly 50 can
comprise non-limiting precursor reservoirs 53, 53' and 53'' feeding
into a mixing chamber 52 which is pumped into the spray apparatus
34 via a mechanical pump 51.
[0071] FIG. 9D schematically illustrates a non-limiting embodiment
of deposition scheme for a spray synthesized material 61 from a
spray device 60 onto a target 63 forming a film 63. The spray
device 64 can comprise a plasma device.
[0072] Direct achievement of films with desired chemistry, phase
and morphology from solution precursors using spray apparatus as
described here has unique attributes. The direct synthesis approach
gives the ability to adjust the chemistry of the catalyst in flight
and in situ. These teachings are not limited to the exemplary
material systems discussed herein and can be employed to many other
material systems.
[0073] An exemplary precursor for nanoscale Al.sub.2O.sub.3
particulate catalyst is aluminum nitrate
(Al(NO.sub.3).sub.3*9H.sub.2O) mixed 1:1 by weight in isopropyl
alcohol. It should be noted that to achieve a pH adjusted solution,
the addition of an acid or a base (dependent on the initial acidity
or basicity) can be used. In some embodiments, the solution can be
pH adjusted to achieve a homogeneous solution wherein the
components contained there are completely dissolved in
solution.
[0074] An exemplary precursor for titania is produced by mixing
titanium isopropoxide with ethanol. Glacial acetic acid and
hydrogen peroxide are used as dispersants.
[0075] Specifically, the aluminum and titanium oxides with varying
ratios of acidity and alkalinity are formed by feeding respective
precursors at varying ratios employing a feeding system illustrated
in FIG. 9C.
[0076] With reference to FIGS. 10A and 10B, the one or more
catalysts can be custom tailored and applied on the reactor
assembly, progressively varying from acidic in nature to mixed to
basic in nature via device 70 of FIG. 10A. According to one
embodiment of the present invention, such customization provides
for by-product selectivity as well as depolymerization
efficiency.
[0077] More specifically, the one or more catalysts of the present
invention can be custom tailored and applied on the electromagnetic
induction coupler of the reactor assembly 80, for example, silver
nanostructures, or nanoparticles, that in presence of oxygen can
perform like osmium tetroxide made in situ. In one embodiment, such
a catalyst could be nano-structured molybdenum designed to catalyze
the partial oxidation of alkenes.
[0078] Further, it has been observed that a depolymerization
reaction according to one embodiment of the present invention can
be effected by nano-scale surfaces--the greatly increased area
available for the reactants and products to bind, as well as the
unique chemistry at the nano-scale open up a new vista in catalytic
de-polymerization. As illustrated in FIG. 10C, such a nano-scale
catalysts 91, 92, and/or 93 can in one embodiment be deposited on
the electromagnetic induction coupler which could be a metal or
non-metal or zeolite like structure 90. The material itself can be
selected from elements like Si, Zr, Cu, Mg, Mn, etc., or oxides
SiO.sub.2, Al.sub.2O.sub.3, ZnO, MgO, BaO, MnO.sub.2,
Fe.sub.2O.sub.3 etc. These can be deposited by precursor plasma or
combustion process according to the current teachings.
[0079] Further solid supported catalysts may be employed as
illustrated in FIG. 10D. In assembly 100, the space between the
electromagnetic induction coupler/impeller blades are filled with
molecular sieves 101 and held in space by a cover screen 102.
[0080] As illustrated in FIG. 11, in some embodiments of the
present invention device 110 can employ a plasma device 111 to
provide heat in addition to the electromagnetic induction field to
depolymerize the polymer feed material, or starting material,
present in chamber 112. The one or more catalysts can be added to
the plasma device along with the polymer feed material, or starting
material, or be supplied to the reactor assembly in accordance with
various embodiments described above, or a combination approach can
be employed.
[0081] In one embodiment, the present invention relates to a method
of depolymerizing polymers, the method comprising the steps of: (i)
providing one or more polymer starting materials, or feed
materials; (ii) providing a reactor to depolymerize the one or more
polymer starting materials, or feed materials, into one or more
monomers; (iii) heating the one or more polymer starting materials,
or feed materials, at a rate of from about 10.degree. C./second to
about 1000.degree. C./second; and (iv) providing an electromagnetic
induction field to facilitate the depolymerization of the one or
more polymer starting materials, or feed materials, into their
constituent monomers, wherein the method utilizes one or more
catalysts that permit in situ reactions to yield one or more
functional monomers.
[0082] In another embodiment, the present invention relates to a
method of depolymerizing polymers, the method comprising the steps
of: (a) providing one or more polymer starting materials, or feed
materials; (b) providing a reactor to depolymerize the one or more
polymer starting materials, or feed materials, into one or more
monomers; (c) heating the one or more polymer starting materials,
or feed materials, at a rate of from about 10.degree. C./second to
about 1000.degree. C./second; (d) providing a coupled
electromagnetic induction field to facilitate the depolymerization
of the one or more polymer starting materials, or feed materials,
into their constituent monomers; and (e) selectively harvesting at
least one of the monomers produced by the method or converting at
least one of the monomers into one or more stable value added
products, wherein the method utilizes one or more catalysts that
permit in situ reactions to yield one or more functional
monomers.
[0083] In still another embodiment, the present invention relates
to a method of depolymerizing polymers, the method comprising the
steps of: (I) providing a polymer starting material, or feed
material; (II) providing a reactor to depolymerize the polymer
starting material, or feed material, into a constituent monomer;
(III) heating the one or more polymer starting materials, or feed
materials, at a rate of from about 10.degree. C./second to about
1000.degree. C./second; and (IV) providing an coupled
electromagnetic induction field to facilitate the depolymerization
of the material, or feed material into its constituent monomer,
wherein the method achieves a yield of constituent monomer of at
least about 80 weight percent based on the extractable weight
percent value contained in the polymer starting material, or feed
material, subjected to depolymerization. In another embodiment,
this method provides a yield of constituent monomer of at least
about 82.5 weight percent, at least about 85 weight percent, at
least about 87.5 weight percent, or even at least about 90 weight
percent or higher based on the extractable weight percent value
contained in polymer starting material. Here, as well as elsewhere
in the specification can claims, individual range values, or
limits, can be combined to form additional and/or non-disclosed
open and closed ranges.
[0084] In still yet another embodiment, the present invention
relates to a depolymerization method that utilizes one or more
customized catalysts to permit and/or facilitate the yield of high
fractions of value added desirable monomers from plastics whose
base monomers are different. A non-limiting example of such a
method of the present invention is obtaining a monomer AB from a
mixture of two plastics (poly-A and poly-B) whose base monomers are
A and B, respectively, or under certain conditions obtaining high
fractions of monomer Y from a plastic (poly-X) whose base monomer
is X.
[0085] The foregoing description of the embodiments has been
provided for purposes of illustration and description. It is not
intended to be exhaustive or to limit the invention. Individual
elements or features of a particular embodiment are generally not
limited to that particular embodiment, but, where applicable, are
interchangeable and can be used in a selected embodiment, even if
not specifically shown or described. The same may also be varied in
many ways. Such variations are not to be regarded as a departure
from the invention, and all such modifications are intended to be
included within the scope of the invention.
[0086] Example embodiments are provided so that this disclosure
will be thorough, and will fully convey the scope to those who are
skilled in the art. Numerous specific details are set forth such as
examples of specific components, devices, and methods, to provide a
thorough understanding of embodiments of the present disclosure. It
will be apparent to those skilled in the art that specific details
need not be employed, that example embodiments may be embodied in
many different forms and that neither should be construed to limit
the scope of the disclosure. In some example embodiments,
well-known processes, well-known device structures, and well-known
technologies are not described in detail.
[0087] The terminology used herein is for the purpose of describing
particular example embodiments only and is not intended to be
limiting. As used herein, the singular forms "a", "an" and "the"
may be intended to include the plural forms as well, unless the
context clearly indicates otherwise. The terms "comprises,"
"comprising," "Including," and "having," are inclusive and
therefore specify the presence of stated features, integers, steps,
operations, elements, and/or components, but do not preclude the
presence or addition of one or more other features, integers,
steps, operations, elements, components, and/or groups thereof. The
method steps, processes, and operations described herein are not to
be construed as necessarily requiring their performance in the
particular order discussed or Illustrated, unless specifically
identified as an order of performance. It is also to be understood
that additional or alternative steps may be employed.
* * * * *